How to tell if installed windows have nailing flange

tngrlNovember 24, 2009

I have single hung aluminum windows installed in a house built in the early 80s. Some neighbors have wooden windows, a few have aluminum and some vinyl. My house is brick with no trim so I can't just remove the trim to see if these have a nailing flange or not. The side jambs do have what appears to be screw holes, but there are no screws in them. Short of removing bricks on the outside is there a way to determine if these have a nailing flange under the brick? I'd like to replace these with vinyl windows, but this will make a huge difference in the labor costs.

If the jamb holes are not used the window is probably secured either with metal straps that extend back into the house and are bent over and nailed to the framing OR a perimeter nail fin was nailed to the exterior sheathing. You can probably tell by removing the interior trim and pulling out any insulation or sealant. Use a strong light (head lamp is best) and a thin probe like an ice pick.